Packaging container



A g- 1961 F. B. STANNARD 2,997,224

PACKAGING CONTAINER Filed Nov. 5, 1958 FOPPA'S 7' B- STANNAED BY a WedA'ITORNEYJ 2,997,224 PACKAGING CONTAINER Forrest B. Stannard, N. HighSt., Clinton, Conn. Filed Nov. 5, 1958, Ser. No. 772,137 6 Claims. (Cl.22953) This invention relates to packaging containers, such as preformedbags or wrappings formed about the articles to be packaged.

The principal object of the invention is to provide a bag or wrapperconstruction which possesses controlled breathing properties. Morespecifically, within the broad objective, is the provision of aconstruction which will permit eflicient sterilization of the contentsof the bag or wrapper after the bag or wrapper has been sealed, andwhich will maintain the contents of the package in a sterile condition.

A further object is to provide a construction and method which isadaptable to a wide variety of packaging forms and procedures and whichis also adaptable to the use of a substantial range of wrappingmaterials including polyethylene film and similar plastic films.

Another object is to provide a construction and method which permitseconomical manufacture, and utilization of conventional machinery forforming, filling and closing the package, or otherwise accomplishing theenclosure of the article in the protective covering.

Other and further objects will be made apparent in the disclosure of theaccompanying drawing and in the following specification and claims.

Many articles or materials which it is desirable or necessary to packageand sell in a sterilized condition deteriorate under heat sterilizationand many wrapping or packaging materials also deteriorate or aredestroyed when subjected to sterilizing temperatures. The existence ofeither one of these conditions precludes heat sterilization of thecontents after the package is sealed, and the pre-sterilization of anarticle or material prior to its enclosure in a wrapper or bag requiresthat the container filling, closing and sealing or wrapping and sealingoperations be carried out under sterile conditions, usually a diflicultand costly procedure, if the sterility of the article or material is tobe preserved.

Gaseous sterilization, while meeting many objections of heatsterilization still has required that the sterilizing gas be introducedinto the package before sealing since conventional wrapping materialsare either impervious to the sterilizing gases, or equally pervious tocontaminating air and other vapors.

By the construction of the invention these limitations tates Patent onthe sterilization of the contents of a sealed package by the gaseousmethod are overcome.

Broadly the invention provides the wall of the bag, wrapper or othercontainer with a portion which is pervious to the passage of sterilizinggases but prevents the entrance of germs.

In the accompanying drawing:

FIG. 1 is a fragmentary plan view of a web of material, embodying theinvention and from which bags, wrappers or other forms of packagingenclosures may be formed;

FIG. 2 is a generally perspective view of a bag embodying the invention;

FIG. 3 is a sectional View substantially on line 3-3 of FIG. 2; and

FIG. 4 is a diagrammatic view illustrating one manner of employing theconstruction of FIG. 1 to form, fill and seal a bag as a continuousoperation.

Referring to FIG. 1 a web, or sheet, of polyethylene, or other moisture,gas and germ impervious material is indicated at 10. A relatively narrowportion of the sheet or web 10 is provided with an overall coating ofheat and 2,997,224 Patented Aug. 22, 1961 pressure sensitive adhesivematerial as indicated at 11. Within the area 11 the web is provided witha plurality of openings as indicated at 12. These openings may takevarious shapes and forms but for reasons hereinafter made apparent theyare spaced longitudinally of the web. Also, as later pointed out, theopenings 12 may be varied in size and shape depending on the nature ofthe material or articles to be packaged.

A web or strip 13 of gas permeable paper is superposed on the web orsheet 10 to overlie the adhesive area 11. The web 13 is of a width to atleast cover the openings 12 and is preferably at least substantiallycoextensive transversely with the area 11. Web 13 extends the fulllength of web or sheet 10. When sterilization of the contents of thecontainer is desired the web 13 will take the form of a germproo-fpaper.

Germproof paper is a dense paper, characterized by its ability to permitthe passage of gases while excluding the passage of germs. Germproofpapers are commercially available, examples being Stock #3930-CKmanufactured by Clairmont Paper Company and Grade #1627 made byMerrimack Paper Company.

Alternatively strip 13 may take the form of a gas permeable paper whichhas been treated with a suitable germicide.

The strip 13 is heat sealed, or otherwise permanently secured to the webor sheet 10 along relatively narrow lines 14, transversely outwardly ofthe openings 12, the portion of strip 13 intermediate the lines of seal14 being left freely separable from the underlying perforated portion ofthe web 10.

The assembly described is economically made in web form as a continuousoperation. The web 10 is continuously advanced past means which appliesthe band of adhesive 11, past means for punching the openings 12, orotherwise renders the portion of the area 11 inwardly of its edgeportions permeable to gases, and past means which position the web 13over the area 11 and past means which heat seals or otherwisepermanently secures web 13 to web 10 along the lines 14. The compositeweb, generally indicated at 15, may then be wound into rolls or cut intosheets depending on the packaging procedure in which it is to be used.

One form of container is shown at 16 in FIGS. 2 and 3. In the formationand use of the container 16 the composite web 15 is run throughconventional folding means, not shown, to form a flat tube having, ifdesired, inwardly extending side gussets 17, the edges of the web 10being overlapped and permanently sealed together at .18 to form thetube, as generally indicated at 19. The opposing walls 20 and 21 of thetube, including the gusset portions 17 may then be sealed or otherwisesecured to each other along a spaced transverse zone 22 and the tube cutat one side of zone 22, as indicated at 23, FIG. 2, to provide an openended bag, which, when filled, may be closed at its open end by atransverse seal line 24.

The overall coating of the area 11 with the adhesive permits the sealingof the paper strip 13 to the underlying portion of web 10 simultaneouslywith the sealing of the opposing plastic surfaces and by the sameinstrumentalities, while the spacing of the openings longitudinally ofthe strips permits location of the seal to assure continuity of thesealed surfaces while keeping the transverse width of the line of sealto a minimum.

Alternatively the composite web 15 may be cut into sheets and fed toconventional bag forming machines which form square-bottom or othertypes of bags. Similarly the web may be fed to various types of wrappingmachines which cut sheets from the web, or receive precut sheets, andfold them around articles and seal the overlapping edges and folds toprovide a sealed wrapped lap-sealed around a hollow mandrel 25 below theend of which the so-formed tube is transversely sealed by a verticallyreciprocating clamping means 26. Material or articles are introducedthrough the hollow mandrel and enclosure thereof completed by thesucceeding transverse sealing operation, the packaging being completedby severing the tube along a line as 27 centrally of the seal at 26.This packaging procedure is exemplified in the disclosure of UnitedStates Patent No. 1,986,422.

The package formed by any of the above, or other, procedures ischaracterized by a capacity for breathing, and for gaseous sterilizationof its contents after the package has been formed, if sterilization isdesired. The sterilizing gas can enter the package through the germproofpaper strip 13 and openings 12 to effect sterilization of packagecontents and excess pressure, if any, built up in the package is laterequalized by escape of excess gases by the same route. The sheet beingimpervious to liquids and gases as Well as germs or othermicroorganisms, protects the contents from subsequent contamination,while germs and other contaminating microorganisms are barred fromentrance through openings 12 by the germpro'of strip 13.

The invention thus makes possible the sterlization of articles afterpackaging in containers formed mainly of transparent plastic sheeting orfilms (such as polyethylene) which are impervious to gases and which areincapable of withstanding sterilizing dry heat or autoclaving withoutdamage. The invention provides in general a package which has thecapacity to breathe and makes possible the economical sterile marketingof many articles desirably sold in transparent containers, such ascotton balls, minor bandage items and the like, which because of thecost of sterile packaging procedures have heretofore been frequentlysterilized, if at all, only prior to packaging.

While the invention has a special utility in extending the use ofpolyethylene film to sterile packaging it will be understood that itsadvantages are not limited to that material, but extends to coatedpapers, foils and other materials which are impervious to moisture andgases and which for various reasons may be found preferable forpackaging specific articles or materials desirably sterilized afterpackaging.

While as shown the gas-permeability is imparted to the area 11 of theotherwise gas impermeable sheet 10 by apertures involving the removingof material it will be understood that if found desirable suchpermeability may be imparted by piercing or cutting which does notremove material, or by other treatment which renders the area 11sufliciently permeable to gases for breathing or sterilizing purposes.

What is claimed is:

1. A sheet construction for forming package wrappings and containerswhich comprises a length of sheet material substantially impervious togases and moisture and having an area of restricted width, extendingfrom one edge to the opposite edge thereof, provided with an overallcoating of heat and pressure sensitive adhesive, said area of the sheetbeing provided with a plurality of spaced openings, and a strip offlexible sheet material, having a limited capacity to transmit gases andmoisture and at least coextensive with said area, heat sealed along itsside edge portions to the side edge portions only of said area, wherebypackages and containers formed therefrom are provided a limited capacityfor breathing.

2. A sheet construction as in claim 1, said length of sheet materialbeing polyethylene film.

3. A sheet construction as in claim 1, said strip of sheet materialbeing germproof.

4. A sheet construction as in claim 3, said length of sheet materialbeing polyethylene film.

5. A sheet construction for forming package wrappings and containerswhich comprises a length of sheet material substantially impervious togases and moisture except along an area of restricted width extendingfrom one edge to the opposite edge thereof, said area being providedwith an overall coating of heat and pressure sensitive adhesive, and astrip of sheet material, having a limited capacity to transmit gases andmoisture and at least coextensive with said area, heat sealed along itsside edge portions to the side edge portions only .of said area, wherebypackages and containers formed therefrom are provided with a limitedcapacity for breathing.

6. A container comprising a flat tube formed of sheet materialsubstantially impervious to gas and moisture except along an area ofrestricted Width extending from one end of the tube to the other, saidarea being provided with an overall coating of heat and pressuresensitive adhesive, and a strip of sheet material, having a limitedcapacity to transmit gases and moisture and at least coextensive withsaid area sealed thereto along its side edge portions, the opposingwalls of the tube including said strip being transversely heat sealedtogether along one end, whereby the container is provided a limitedcapacity for breathing.

References Cited in the file of this patent UNITED STATES PATENTS2,386,157 Barthen Oct. 2, 1945 2,634,856 Perkins Apr. 14, 1953 2,647,334Wilsher et a] Aug. 4, 1953 2,664,358 Eichler Dec. 23, 1953

